Automobile door locking and unlocking means



AUTOMOBILE DOOR LOCKING AND umocxmc MEANS 1 A. A. GUST June 11, 1957 2Sheets-Sheet 1.

Filed 001.. 4,

z u m m m m m m 2 flfi w w 6 f a INVENTOR. (Z6014 GM 3W, ;2,,BM $73MJune 11, 1957 A. A. GUST AUTOMOBILE DOOR LOCKING AND UNLOCKING MEANS 2Sheets-Sheet 2 Filed Oct. 4. 1954 INVENTOR. Q ZW Q 1246M, 3% $94M UnitedStates Patent AUTOMOBILE DOOR LOCKING AND UNLOCKING MEANS Alex A. Gust,Waukeg'an, Ill.

Application October 4, 1954, Serial No. 460,034

9 Claims. (Cl. 70-464) The present invention relates to means forautomatically locking and unlocking'a plurality of locks from a singlecontrol station, and particularly, to means for automatically lockingand unlocking all of the doors of an automotive vehicle by the simpleexpedient of locking and unlocking one door.

I am aware that certain proposals have been made heretofore in regard tomeans of the general character defined, but in such proposals, the doorlatching means as well as the ineans for barring or locking the latchwere intended to be automatically actuated, which, of course, presentssubstantial problems with respect to the power required to unlatc'h thedoor and the great expense involved in endeavoring to provide all of thenecessary 'instru-meutalities, and to provide instrumentalit-ies of therequisite power. Because of these and other problems and disadvantagesinherent in the prior proposals in the art, automatic door locking andunlocking means of the character referred to have failed to attainpracticality and have not been commercially acceptable.

it is an object of the present invention to provide improved doorlocking and unlocking means of a commercially practical and highlyeconomical nature.

In distinction to the prior endeavors in the art, the present inventionis not concerned with the provision of means forautomatically latchingand unlatching doors, but, instead, has for its object the provision ofmeans for rendering the door unlatching means operative and inoperative,thus to accommodate and prevent, respectively, openingof the doors, theoperativeness and inoperativeness of all of the vehicle doors beingcontrolled from a single door.

According 'to the invention, I provide, for example in a four-doorpassenger vehicle, three of the doors with controllable f'r'neansaccommodating or preventing actuation of the door unlatching means, andthe fourth door with the control means for the other three. In anautomotive vehicle equipped with a storage battery, the most convenientand economical power for elfeoting control functions is electrical powerderived from the battery, particularly since utilization of electricalpower does not require that the vehicle "engine be in operation. 'In thepreferred embodiments of my invention, the said conthe vehicle battery,when the door is unlocked and locked. The other three doors each includea lock bolt for barringthe door latching means, a solenoid operable torelease'the lock bolt, and a normally open switch for ice , handle isinitially operated, the switch associated there with is closed toenergize the solenoid to release the lock bolt, whereupon the door maybe unlatched manually by continued movement of the handle. However, ifthe front right hand door were locked, the solenoid could not beenergized, and the lock bolt would prevent unlatching and opening of thedoor. a f

The structure defined affords the particular advantages that it does notin any way interfere with opening of the doors from the inside of thevehicle, at least one door can be opened, by means of the key, from theoutside of the vehicle even if there is a power failure, door latchingand iinlatching is eifected entirely conventionally, and there is noneed to close the ignition circuit, operate the vehicle engine, orotherwise control door operation from the operators position at thesteering wheel of the vehicle. All of the vehicle doors, when closed,are automatically locked when the right hand front door is locked, andare all rendered operable upon unlocking of that single door.

In addition to the foregoing, it is an object of the invention toprovide an improved door locking and unlocking means of the characterdescribed of a simple, compact, inexpensive and efficient nature,wherein the said switches, solenoids and lock bolts, due to the compactness thereof, are incorporated directly in the respective door handle.

A further object of "the invention is the provision of improved means ofthe character above defined, wherein the said switches, solenoids andlock bolts may readily and conveniently be installed in the existinghandles and door structures of vehicles.

As will be appreciated, the accomplishment of said objects affords theadvantages of particular economy and commercial practicality, andfacilitates the even more c'oiuienient use and operation of modernvehicles.

Other objects and'advantages of the present invention willbecomeapparent in the following detailed description of a preferredembodiment of the invention.

Now, in order to acquaint those skilled in the art with the manner ofmaking, installing and using the door lockingfand unlocking means of theinvention, I shall describe, in connection with the accompanyingdrawings, a preferred embodiment of the invention and a preferred modeof constructing the same.

In the drawings, wherein like reference numerals in- 'dicate like parts;

Figure 1 is "a somewhat schematic circuit diagram of the electricalarrangement provided according 'to the invention to accommodateautomatic unlocking and lockin'g'ofthe four doors of a vehicle throughthe instrumentality of a-single door lock;

"Figure 2 is a bottom view, partly in plan and partly in "section, of avehicle door handle equipped with the master control instrumentalit-y ofthe invention, a portion "of the vehicle door and door latching meansbeingshown "in dotted lines;

Figure 3 is a fragmentary horizontalsection of a'doo'r handle equippedwith controllable means provided according to the inventionfor--automatically rendering the door unlatching means operative andinoperative;

.Figure 4 is a fragmentary sectional view taken substantially onthe line-44 of Figure 3; and

26 fitting and secured within the door structure.

being electrically connected to one terminal of the battery,

and the other battery terminal being grounded, as is conyentional; Theswitch is incorporated in one door of the vehicle, preferably, in themanner shown in Figure 2 and to be described indetail hereinafter. Theother three and a solenoid 16, the switch and solenoid in each doorbeing electrically connected in series with one another and, as a unit,being connected in series with, the master switch unit or :assembly ispreferably incorporated in a door handle in the manner shown in Figures3 to 5, to be de-,

scribed hereinafter. As will be appreciated from the .circuit diagram,closing of the switch 10 will not directly ing and unlocking of all ofthe doors automatically and simultaneously, as will appear more fullyhereinafte'n Referring now to Figure 2, one vehicle door and handle areshown within which a preferred embodiment of the master switch 10 isincorporated. The door shown in Figure 2 preferably comprises the righthand front door of the vehicle, butmay, if desired, comprise any door ofthe vehicle. The door handle illustrated, indicated generally at 20, isof a type employed extensively in the automotive industry at this timeand is substantially conventional. The handle 20 includes a hand gripportion 22, spaced from the outer surface of the vehicle door, shown indotted lines and indicated at24, which portion of the handle terminatesat one end, its rearward end, in a stud At its opposite or forward end,the handle includes a tubular portion 28.having areduced extension 30also fitted and held within the door structure. The stud 26 andextension 30 retain the handle fixed on the door against relativemovement, and the door latch is-adapted to be actuated bymeans of a pushbutton 32 reciprocable in the tubular portion 28 of the handle. The pushbutton is operatively associated with a rectangular rod or plunger 34which extendsinto the door latch mechanism, outlined in dotted lines andindicated generally at 36, (to actuate the door latch 38, also shown indotted lines. The latch mechanism does not form part of the presentinvention and the same is publicly known. Sufiice it to say that, with.the door unlocked, inward movement of the push button 32 effectswithdrawal of the latch 38 to accommodate opening of the door uponexertion of anoutward pull on the hand grip 22. A lock of a conventionaland known nature, forming no direct partof this invention, isincorporated in the conventional manner in the push button 32, the lockbeing provided with a key 40to facilitate locking and unlocking of thedoor from the exterior of,

maybe opened at any time, in an entirely conventional manner, even ifthere is a failure of electric power supply.

doors of the vehicleare each equipped with a switch 14 1 '10individually or separately of the'other switches 14 and solenoids 16 ofthe circuit. Each'switch and solenoid To incorporate the masterswitch'10 in the handle 20, I prefer to mount the same directly withinthe tubular portion 28 of the handle and to actuate the switch inaccordance with the rotary movement imparted to the lock, or the movableportion or bolt thereof, upon locking and unlocking of the door. By wayof example, a preferred master switch 10 comprises a stationarycupshaped member 42 fitted into the tubular portion 28 of the handle andretained therein by means of a C-ring 44 or the like fitting within acircumferential groove in the inner wall of the tubular portion 28.Preferably, the cup-shaped member is formed of insulating material andincludes a pair of diametrically opposed ears fitting withinlongitudinal grooves 46, conventionally provided in the inner wall ofthe handle portion 28, to retain the member 42 against rotation. Thecup-shaped member is centrally apertured to accommodate passage of theplunger 34 and, to opposite sides of the plunger, carries a pair of 1contacts 48, which are supported in insulated spaced relation by themember 42. The contacts 48 each comprise the terminals of electrical,conductors 50 which constitute, in effect, the lead from the battery 12to the switch 10 and from the switch 10 to the switches 14 in thecircuit diagram of Figure 1. Within the cup-shaped member 42, a secondinsulating member or disc 52 is rotatably mounted, the disc having acentral opening complemental to the cross section of the rod 34, wherebythe disc is rotatable with the rod. The disc 52 of insulation alsocarries a pair of contacts 54 and a conductor 56 extending between andelectrically connecting the contacts. When the door is unlocked, as isshown in Figure 2, the contacts 54 engage the contacts 48, and theconductor 56closes the circuit between the conductors 50, thus to closethe master switch 10. Upon locking of the door, the rod 134 and disc 52are turned or rotated to such extent as to able switch. member or blade52, 54 and 56 with the stationary contacts 48, a compression spring 58is preferablyconfined between the push button 32 and the disc 52 to biasthe disc into engagement with the contacts 48. Also, the spring 58 willnormally serve to bias the push button to its outermost position, and toreturn the push button to such position after unlatching of the door.

The main switch 10 thus provided is of very simple and inexpensiveconstruction and assembly, and the same is sufficiently compact tofacilitate mounting thereof directly within the handle 20. Installationof the switch is rapidly and conveniently effected and requires nochange 'in the handle.

Since the switch is only required to be closed when the door is unlockedand open. when the door is locked, it will be appreciated'that otherswitch forms may be employed with equal facility, and that other formsof switches may be required for difierent forms of latch operatingmeans.

The mounting of controllable solenoid means according to the presentinvention in a switch handle is shown in a preferred embodiment inFigures 3 to 5. The door structure and the latching mechanism are .ofthe same character and structure shown in Figure 2 and described inconjunction therewith, and because of this identity, the door and latchare not indicated in Figure 3. Likewise, only a portion of the doorhandle 20 is shown, the handle including, as previously described, ahand grip 22, a tubular front portion 28 and extension 30 havinglongitudinal grooves 46" in the inner wall thereof, and a push button32. The handle differs from that previously described in that the handleis not provided with a key lock and does not include the identical latchoperating plunger above described. In this construction, the push button32 has an imperforate outer end wall and is otherwise tubular, and ismounted for reciprocal movement within the tubular handle portion 28. A

solenoid coil 60 is mounted within the hollow interior of amatt thepushbutton, the same including a spool 62, formed of insulatingmaterial, upon which the wire of the coil is wrapped. Suitably, thespool 62 is retained within the push button, in engagement with the endwall thereof, by turning portions of the side wall of the buttoninwardly at the lower or inner end of the button, as is indicated at 64.At the upper end of the coil, one terminal of the coil wire extendsthrough the spool to be grounded on the push button, as is indicated at'66. The other terminal of the coil wire, at the lower end of the coil,extends through the spool 62 and is electrically connected to adepending, elongate contact rod. The contact rod 68 is physicallycarried by the spool 62 and extends longitudinally downwardly 'orinwardly therefrom through the tubular portion 28 and extension 30 ofthe handle in spaced parallel relation to the axis of said portion. Thespool 62 is tubular, or has a hollow core, within which a rod-like,magnetic armature 70 reciprocates, the armature being magnetically drawnupwardly into the spool core upon energization of the coil, and beingbiased downwardly and outwardly out of the spool core upondeenergization of the coil by means of a compression spring 72, which isconfined between the push button 32 and the top surface of the armature.

To connect the push button 32 to the door latching mechanism, a tubularplunger 74 extends inwardly or downwardly from the push button towardthe latch mechanism. The plunger 74 may be operatively connected infixed relation to the push button in several ma'nn'e'rs. For example, Ihave shown a strong coil spring 76 retaining an end flange of the tubein engagement with the lower surface of the solenoid spool 62. Adjacentits inner or lower end, the tubular plunger 74 may suitably be providedwith diametrically opposed slots 78 in the side walls thereof adaptedfor the reception of the di'ametrical tabs 80 of a plunger extension 82.The slot and tab association of the plunger 74 and its extension 82accommodates axial offset of the plunger with respect to the latchmechanism, and also accommodates lengthwise adjustment of the plunger.In operation, when the push button 32 is depressed, the push button,

the solenoid coil and the plunger 74 are adapted to be moved inwardlytoward the latch mechanism until the extension tabs Sil are engaged bythe plunger at the end wall of the slot 78, whereupon the extension 82is moved inwardly to effect the unl'a tching operation. To control suchoperation, the present inventionprovides a lock bolt in the handlecooperable with the tubular plunger 74. To accommodate such lock bolt,an inverted cup-shaped member 84, preferably formed of insulatingmaterial, is inserted in the lower end of the tubular extension 30 ofthe handle. The member 84 includes diametrically opposed ears 86 fittingwithin the longitudinal grooves 46 in the tubular portion of the handleto retain the member against rotation in the handle. The cup-shape ofthe member 84 defines a. chamber which is closed at its lower end bymeans of a disc 88, also preferably formed of insulating material, whichis fitted and retained against rotation in the handle in the same manneras the member 84. A C ring 90' or the like seating within acircumferential groove in; the inner wall of the extension 30 normallyretains the members 84 and 88 in the handle. These members are providedwith aligned bores adjacent one edge thereof accommodating passagetherethrough of the contact rod". 68. Likewise, the members arecentrally apertured to accommodate passage of the tubular plunger 74,the disc 88 preferably including an axial sleeve 92 surrounding theplunger '74. This sleeve affords a particular con-- venient mounting fora stationary contact, in that the: sleeve is provided with acircumferential groove therein adapted to receive agenerally -C-shapedspring contact: clip 94 connected to the outer end of an electricalconcluster 96. The conductor 96 comprises one lead from.

the main switch 10, and is a continuation of oneof the".

6 conductors '50 shown in Figure 2. The contact clip 94 includes freeend portions projecting beyond the 'sleeve 92 and disposed in alignmentwith the contact rod 68, so that upon depression of the push button 32,the rod 68 engages the contact 94 to close (if the main switch 10 isclosed) the electrical circuit through the solenoid coil 60.

As thus confined within the handle, the member 84 affords a fixedsupport or base wall against which the spring 76 may bear to "retain thetubular plunger 74 in operative engagement with the push button, andalso to retain the push button normally in its outermost position.

Within the chamber defined by the member 84 and disc 88, a lock bolt orobstruction block 98 is mounted for sliding movement transversely of thetubular plunger 74. As shown in Figure 5, the lock bolt comprises agenerally U-shaped member straddling the plunger 74. A leaf spring 100is embedded at one of its ends in the lock bolt and at its other endengages the wall of the member 84 normally to bias the lock boltradially inwardly toward the plunger. At the portion thereof normallyreceived within the chamber in the cup-shaped member 84 and sleeve 92,the side wall portion of the tubular plunger facing the bight portion ofthe U-shaped lock bolt 98 is cut away, as shown in Figures 3 and 4, todefine a right angle abutment edge 102 at the upper or outer end of thecut-away portion, and an inclined surface 104 adjacent the lower endthereof leading into and inwardly or downwardly extending slot 106 inthe side 'wall of the tube. The spring 100 normally biases the bightportion of the lock bolt 98 into the cut-away portion of the tube, sothat upon partial depression of the push button, the abutment edge 102of-the plunger 74 normally engages the lock bolt 98 to prevjent inwardmovement of the plunger and unlatching of the door. Such slight inwardmovement of the plunger is accommodated without resulting in unlatchingof the door by the slot and tab connection of the plunger 74 and itsextension '82.

To effect release of the plunger 74, and thus to accorn'modateunlatching of the'door, the solenoid armature 70 comprises an elongatedsolid rod extending through and guided by the tubular plunger 74. At thecut-away portion of the tube 74, the armature rod 70 is similarly cutaway, that is, in the portion thereof normally coextensive with thecut-away'portion of the tube 74, to define :a right angle abutment edge108 at the upper end of the cut-away and an inclined cam surface 110 atthe lower end of the cut-away. Instead of being slotted, the rod '70,immediately below the cam surface 110 thereof, includes a radiallyoutwardly extending projection 112 which is normally received within theslot 106 in the tube 74 and which includes a surface 114 constituting acontinuation of the cam surface 110. The armature 70 is thus heldagainst rotation with respect to the plunger 74 and :obstruction blockor lock bolt 98 by the projection 112 acting within the cut-away portionand slot 106 of the plunger. The cam surfaces 110 and 114 of thearmature 70 are adapted to engage the lock bolt 98, and the lock boltmay suitably be provided with a complemental cam :su'rface 116 at theinner lower edge of'the bight portion thereof.

Assuming the main switch 10 is closed, i e., that the from right handdoor of the vehicle is unlocked, whether e'the vehicle door be opened orclosed, opening of another vehicle door is accomplished as follows: thepush button 32 is pressed inwardly to move the coil 60, contact rod 68and plunger 74 inwardly, such inward move- :ment being accommodated byclearance between the abutment edge 102 of the plunger and the lock bolt98. Such movement as is accommodated by the "said clearance results inthelower or inner end of the contact rod 68 being moved into engagementwith the contact clip 94, whereupon the electrical circuit is closedfrom the battery .12 through the switch 10, conductors 50 and 96, clip94, rod 68 and coil 60 of the solenoidto ground, to energize thesolenoid. When the coil of the solenoid is energized, the armature 70 ismagnetically pulled into the coil, thus moving the cam surfaces 110 and114 on the armature upwardly or outwardly toward the lock bolt 98. Asthe cam surface 110 engages the cam surface 116 of the lock bolt, thelock bolt is moved radially outward against the bias of the spring 100,and such movement continues as the cam surfaces 110 and 114 progressupwardly, thus to move the bight portion of the lock bolt out of thecut-away portion and out of the path of the plunger 74. 1 The upwardmovement of the armature is limited by engagement of the projection 112.with 'the abutment edge 102 of the plunger 74, whereby the armature andits projection prevent reentry of the lock, boltinto the cut-awayportion of the plunger while the solenoidis energized. With the lockbolt 98 thus released, further inward movement of the push button andplunger is accommodated. During such movement, the solenoid coil andarmature are moved inwardly with the plunger to clear the lock. bolt 98,whereafter the lock bolt rides. on the imperforate surface of theplunger outwardly of the cut-away portions thereof, such inward movementresulting in compression of the spring 76.

V Also, during the further or continued inward movement of the plunger,the contact rod 68 is moved downwardly or inwardly, and to accommodatethis movement, the contact clip 94 includes flexible or resilient endportions through which the contact rod may pass. The contact rod may beexposed or bare throughout its length -to be engaged by the clip 94 tomaintain the solenoid energized during the entirety of door unlatchingmovement of the handle. However, because of the tendency of users tohold the push button in or depressed a longer length of time than isrequired and to minimize energization of the solenoid, and to eliminateunnecessary energization of the solenoid, I prefer to insulate all but asmall end portion of the rod 68 by means of an insulating tube 118. Theexposed end portion of the contact rod 68 is of a length to insureenergization of the solenoid during the portion of movement required todisposed the imperforate portion above the edge 192 of the plunger 74 inalignment with the lock bolt 98, whereafter the solenoid may bedeenergized by disposing the insulation 118 between the contact rod 68and the contact clip 94. Upon deenergization of the coil 60, the spring72 moves .the armature 70 inwardly of the plunger 74 to dispose theprojection 112 in the bottom of the slot 106.

Upon continued inward movement of the push button I 32 and plunger .74,the end wall portions. of the plunger 74 bounding the slot 78 thereinengage the tabs 80 of the plunger extension 82 to move the extensioninwardly to effect unlatching of the door in a conventional manner. Apull may then be exerted on the hand grip 22 to open the door, whereuponthe push button 32 may be released. As the push button ,is released, thespring 76 returns the push button "32, coil 60, contact rod 68, armature70 and plunger 74 outwardly or upwardly to release the extension 82 andthe door latch. Adjacent the end of spring effected movement, thesolenoid may be instantaneously energized by passage of the. exposed endof the contact rod 68 through the clip 94, but such energization is ofsuch short duration as to impart no appreciable movement to the armature70, and even if it did, no harm would be done. Also adjacent the end ofspring effected movement, the abutment edge 102 of the plunger 74 clearsthe lock bolt 98, whereupon the lock bolt is returned to its plungerblocking position by the spring 100. Thereafter, if the main switchremains closed, the other doors may be opened at any time in the mannerdescribed, ..but if the main switch 10 is opened, by locking the righthand front door of the vehicle, the lock bolt 98 will prevent operationof the latches of the other doors.

preferred embodiment of the invention are simple, inexpensive andcompact, so compact in fact as to be mounted directly within therespective door handle. Further, the construction is such that the meansof the invention may conveniently and economically be installed inexisting door handles without modification or reconstruction of thehandles. Specifically, with either of the structures shownin Figures 2and 3, the components of the apparatus of the invention are inserted inthe handle in the order indicated, whereafter the components are securedwithin the respective handle by means of the C-rings 44 and 92. In thestructure of Figure 2, the conductors are quickly united to the contacts48 in a conventional manner. In the structure of Figure 3, the contactclip 94 and conductor 96 are readily associated with the apparatusmerely by slipping the contact clip over the sleeve 92 and fitting thesame within the circumferential groove in the sleeve. Further, theelectrical wiring re quired is of the simplest nature and is readilyinstalled in known manners by anyone acquainted in the art.

In addition to the above, the present invention affords automatic, doorlocking and unlocking means that in no way interfere with theconventional and intended operation of the vehicle doors. The doors maybe opened from the interior of the vehicle in an entirely conventionalmanner. The door in which the master switch is incorporated is operatedentirely manually, and does not rely onany electrical energization.Should the battery of the vehicle go dead, this door may still be openedfrom the exterior of the vehicle, and the remainder of the doors, thoughlocked from the outside, may be opened from the interior of the vehicle.Also, all doors may be closed at any time, whether the main switch isopen or closed, since the means and apparatus of the invention do notblock the door latch per se. The invention has been describedprincipally with respect to the doors of a four-door passenger vehicle,but it is to be appreciated that the invention is equally applicable totwo or more doors in any vehicle, to two-door vehicles, and ,to thepassenger and cargo doors of commercial vehicles.

With respect to the power requirements of the solenoid control means, itis to be observed that the lock bolt 98 is a particularly small memberand that the only force resisting movement thereof is the leaf spring100, which need not be a particularly strong spring. Secondly, the camsurfaces 110 and 114 provided on the solenoid armature 70, and the camsurface 116 provided on the lock, bolt, afford a substantial mechanicaladvantage in moving the lock. bolt laterially of the tubular plunger 74.In view'of these considerations, it is to be appreciated that thesolenoid coil need not set up a particularly powerful magnetic field.Further, since the handle 20 is normally located in a horizontal plane,the armature of the solenoid is also disposed horizontally, so that thesolenoid coil is not required to lift a weight, thus further minimizingthe power requirement of the solenoid coil. In addition, in thepreferred embodiment, the solenoid is only energized momentarily, i. e.,sufficiently to move the armature to the extent necessary to move theprojection 112 into engagement with the abutment edge 102 of theplunger. Accordingly, it is to be appreciated that the powerrequirements of the solenoid coil are only momentary for each opening ofthe door and that the power requirement is quite low.

While I have described what I regard to be a preferred embodiment of myinvention, it is to be appreciated that various changes, rearrangementsand modifications may be made therein without departing from the scopeof the invention, as defined by the appended claims.

I claim:

1. Means for simultaneously locking and unlocking a plurality of doors,one of the doors comprising a :master door and having a latch, a handlefor operating the latch and a lock for locking and unlocking the .door,the other doors each having a latch and a handle for operating thelatch, said means comprising, a combination, a single master control inthe master door, said master control constituting the soleinstrumentality of said means in said master door, and controlledenergizable means in each of the other doors interposed between thehandle and the latch of the respective door, said controlled energizablemeans when not energized preventing and when energized accommodatingunlatching of the respective door latch by the respective handle, saidmaster control being connected in series with a source of power and witheach of said controlled energizable means, said master control beinoperatively associated with the lock in the master door to accommodaterelease of power to each of said controlled energizable means when themaster door is unlocked and to prevent the su ply of power to each ofsaid controlled energizable means when the master door is locked.

2. Means for simultaneously locking and unlocking a plurality of doors,one of the doors comprising a master door and having a latch, a handlefor operating the latch and a lock for locking and unlocking the door,the other doors each having a latch and a handle for operating thelatch, said means comprising, in combination, a single manually operatedmaster control in the master door, said master control constituting thesole instrumentality of said means in said master door, and controlledenergizable means in each of the other doors interposed between thehandle and the latch of the respective door, said controlled energizablemeans when not energized preventing and when energized accommodatingunlatching of the respective door latch by the respective handle, saidmaster control being connected in series with a source of power and witheach of said controlled energizable means, said master control beingoperatively associated with the lock in the master door to accommodaterelease of power to each of said controlled energizable means when themaster door is unlocked and to prevent the supply of power to each ofsaid controlled energizable means when the master door is locked, eachof said controlled energizable means including a secondary control inthe respective door in series with the source of power and said mastercontrol, said secondary controls each being operatively associated withthe handle of the respective door to be operated upon door unlatching vmovement of the respective handle to release power to, when the mastercontrol accommodates release of power, and energize the respectivecontrolled energizable means to accommodate unlatching and opening ofthe respective door by the respective handle.

3. Means for simultaneously locking and unlocking a plurality of doorseach having a latch and a handle for operating the latch, only one ofsaid doors having a lock for locking and unlocking the same, said meansconsisting of a single manually operated master switch to be disposed inthe said one door and operatively associated with the lock thereof to beopen when the said one door is locked and closed when the said one dooris unlocked, a normally open secondary switch to be disposed in each ofthe other doors and operatively associated with the handle thereof to beclosed upon door unlatching movement of the respective handle, andelectrically energized means to be disposed in each of the said otherdoors operatively between the latch and the handle of the respectivedoor, each of said electrically energized means to be disposed normallyto prevent operation of the respective latch by the respective handleand, upon energization, to accommodate operation of the respective latchby the respective handle, the secondary switch and the said electricallyenergized means in each of the said other doors to be connected inseries and to be connected as a unit in series with said master switchand a source of electric power individually of the secondary switch andelectrically energized means in the other ones of the said other doors.

4. Means for simultaneously locking and unlocking a plurality of doorseach having a latch and a handle for operating the latch, only one ofsaid doors having a lock for locking and unlocking the same, said meanscomprising a master switch to de disposed in the said one door andoperatively associated with the lock thereof to be open when the saidone door is locked and closed when the said one door is unlocked, saidmaster switch constituting the sole instrumentality of said means insaid one door, a normally open secondary switch to be disposed in eachof the other doors and operatively associated with the handle thereof tobe closed upon door unlatching movement of the respective handle, asolenoid to be disposed in each of the said other doors, and a lock boltto be disposed in each of the said other doors operatively between thelatch and the handle of the respective door normally to preventoperation of the respective latch by the respective handle, thesecondary switch and solenoid in each of the said other doors to beconnected in series with one another and to be connected in series as aunit with said master switch and a source of electric power individuallyof the secondary switch and solenoid in the other ones of the said otherdoors, each of said solenoids to be operatively associated with the lockbolt in the respective door to move, upon energization thereof, therespective lock bolt to accommodate operation of the respective latch bythe respective handle.

5. In a door having a latch and handle assembly including a push buttonfor operating the latch, a tubular plunger extending between the pushbutton and the latch operatively to connect the same, said plungerhaving a cut away portion defining an abutment edge to the side thereofadjacent the push button, a laterally movable lock bolt mounted in thehandle and normally extending into said cut-away portion to be engaged'by said abutment edge to prevent movement of said plunger by the pushbutton thus to prevent operation of the latch, a solenoid coil on saidplunger between the push button and said cut-away portion, and asolenoid armature reciprocable in said plunger to be moved toward thepush button upon energization of said coil, said armature including acam surface to the side of said lock bolt away from the push button andfacing toward said lock bolt and the push button, said cam surface beingcooperable with said lock bolt upon energiz' tion of said coil to movesaid lock bolt laterally outward of said abutment edge to release saidplunger to accommodate operation of the latch by the push button.

6. Door locking and unlocking means for a first door having a latch, ahandle for operating said latch and a lock for locking and unlocking thedoor, and a second door having a latch and a handle for operating saidlatch, said means comprising a switch in said first'door operativelyassociated with said lock to be closed when said door is unlocked andopen when said door is locked, said switch comprising the soleinstrumentality of said means in said first door, a lock bolt in saidsecond door normally preventing unlatching of the latch of said seconddoor by the handle thereof, a solenoid in said second door operativelyassociated with said lock bolt to release said lock bolt when energized,and a normally open switch in said second door operatively associatedwith the handle thereof to be closed during door unlatching movement ofsaid handle, said solenoid and said switches being connected in serieswith an electric power source.

7. A handle for actuating a door latch comprising a manually operablemember to be operatively associated with the latch, a lock bolt in thehandle operatively related to said member and normally preventingoperation of the latch by said member, electro-magnetic means mounted inthe handle concentric with said member, said electromagnetic means beingoperatively associated with said lock bolt to eflect retraction ofisaidlock bolt when energized, said lock bolt when retracted accommodatingactuation of thelatch by said member, and a normally open switch'in thehandle in series with said electromagnetic means, said switch includinga stationary contact mounted in the handle and a movable contact carriedby said member, said movable contact being moved by said member towardengagement with said stationary contact upon movement of said member toactuate the latch.

8.In a handle for a door latch, a generally tubular housing, a hollowmember movably mounted in said housing concentric therewith foractuating the door latch, an t electromagnetic coil mountedconcentrically in said memher, and a lock bolt in said housingoperatively related to said member and the normally preventing actuationof the latch by said member, said electro-magnetic coil beingoperatively associated with said lock bolt to effect retraction of saidlock bolt upon energization of said coil to accommodate operation of thelatch by said member.

9. In a handle for a door latch, a generally tubular housing, a hollowmember movably mounted in' said housing concentric therewith foractuating the door latch, a solenoid coil mounted concentrically in saidmember, a solenoid armature slidably mounted in said coil concentricallytherewith, and a lock bolt insaid housing movable generallyrtransverselyof said armature, said lock bolt normallytbeing disposed in the path ofmovement of said member normally to prevent actuation of the latch bysaid member, said armature being operatively associated with said lockbolt to effect retraction of said lock bolt upon energization of saidcoil to accommodate operation of the latch by said member.

References Cited in the file of this patent UNITED STATES PATENTS2,006,624 Block July 2, 1935 2,329,309 Ward Sept. 14, 1943 2,371,370Ward Mar. 13, 1945 2,466,481 Royal Apr. 5, 1949

